Dopaminergic dysfunction in tourette syndrome

Abstract
A prospective clinical and biochemical study on the effects of treatment with haloperidol has been performed in seven patients with Tourette syndrome. Pretteatment cerebrospinal fluid levels of homovanillic acid (CSF HV A) were significantly reduced in all patients, whereas 5-hydroxyindoleacetic acid was reduced in only two. With haloperidol treatment, symptoms decreased in all cases (21 to 88%) and clinical improvement was associated withan increased level of CSF HV A, often returning to the normal range. Optimal therapeutic response was found with serum levels of haloperidol between 1 and 4 ng/ml; however, disturbing side effects also occurred within this range. These results support the hypothesis that Tourette syndrome may result form a supersensitivity of dopaminergic receptors.